Presented as entries in a diary, Cole's (The Dragon in the Cliff) novel focuses on the predicament of the mostly wholesome Valerie, who gets pregnant the very first time she has intercourse (she repents of her sex life, incidentally, even before she realizes she's pregnant). After a couple of months of worry and denial, the teenager faces up to her condition. She and her boyfriend, Peter, investigate the possibility of abortion, but quickly decide to marry and raise the baby together. Peter's father, however, exiles him to a boarding school, and Valerie's parents, meanwhile, encourage her to put the baby up for adoption. Cole assembles an impressive array of solid information. Quite often, these facts come adroitly camouflaged: the issue of childproofing a house, for example, is tackled in the context of a classroom discussion that Valerie cites to prove how tiresome the teacher is (``How these discussions are supposed to teach us anything is beyond me,'' Valerie concludes). But despite the profusion of down-to-earth details, the unswerving, didactic agenda prevents the novel from becoming as intensely personal as many works on this subject, e.g., Berlie Doherty's Dear Nobody. Ages 10-up. (Apr.)